From before, there have been needs to examine circumstances of contamination by microorganisms in air and on wall surfaces and floor surfaces of hospitals, food factories, and other locations where particular attention must be paid to sanitation as well as to examine circumstances of contamination by microorganisms of utensils and clothing used for surgery and food manufacturing (Non-Patent Document 1). In a conventional method, a sample is coated as a solution onto a culture medium or a membrane having a plurality of cells fixed thereon, formation of colonies by a microorganism or loss of the cells spread in the form of the membrane due to a virus is made to occur, and evaluation is performed by counting the number of colonies or number of loss (Non-Patent Document 2).
Meanwhile, by advances made in single-molecule DNA manipulation and measurement arts through progress of technical development in recent years, it has become possible to make clear observations by fluorescently staining of single-molecule DNA (Non-Patent Document 3). Using this art, it is becoming possible to take out a DNA molecule from a cell, extend and fix the DNA molecule on a substrate, and adhere a fluorescently stained restriction enzyme to the extended and fixed DNA to prepare a restriction map using a fluorescence microscope (Patent Document 1 and Non-Patent Document 4).    Patent Document 1: Japanese Published Unexamined Patent Application No. 2003-200400    Non-Patent Document 1: U Yanagi: “Behavior of bio-aerosol in office buildings and methods of control,” Green Technology, vol. 17, No. 5, 44-47, 2007    Non-Patent Document 2: Sumiyo Ishimatsu: “Capture and detection of airborne microorganism particles,” Green Technology, vol. 17, No. 5, 48-51, 2007    Non-Patent Document 3: Morikawa K., and Yanagida M., J. Biochem., 89, pp. 693-696, 1981    Non-Patent Document: A. Bensimon, A. Simon, A. Chiffaudel, V. Croquette, F. Heslot, D. Bensimon, “Alignment and sensitive detection of DNA by a moving interface,” Science, Vol. 265(5181), pp. 2096-2098, 1994